1. Field of the Invention
The present invention relates to a brake apparatus for an electric corner module (ECM) in which planet gears are moved in an axial direction using a driving unit so as to induce friction between a housing and the planet gears and thus confinement forces of the planet gears are generated so that a brake function can be implemented by blocking power transmission using a decelerator.
2. Discussion of Related Art
In general, in electric vehicles or hybrid vehicles, unlike internal-combustion engine vehicles, a motor is mounted in a wheel for power transmission and driving of the motor is used as a power source.
There is an electric corner module (ECM) or an in-wheel motor as a power transmission system having the structure.
Also, the power transmission system described above uses a decelerator so as to obtain a large driving force.
The decelerator is configured in such a way that a linear gear is mounted on a wheel shaft and a ring gear is disposed at a housing and a planet gear carrier including a plurality of planet gears that engage with the linear gear and the ring gear is installed at a wheel hub and if the ring gear is fixed and the linear gear is driven, the planet gear carrier is decelerated.
That is, if an electric power source is applied to a stator of the motor, a rotor is driven and power is transmitted to the rotor, the linear gear is rotated. In this case, the planet gears are rotated along an inner surface of the ring gear, and the planet gear carrier drives the wheel so that the wheel is decelerated and a large driving force can be obtained.
However, a power transmission system having one of structures of the conventional in-wheel motor as well as the conventional ECM described above is configured so that general brake apparatuses, such as a motor brake, a caliper, and a drum brake, are installed in the wheel.
Thus, since the power transmission system and general brake apparatuses need to be disposed together in the wheel, the size of the power transmission system is limited.
Also, when a separate caliper or drum is introduced, part of the performance of the motor or the decelerator may be lowered, or brake performance may be degraded. In addition, the size of the wheel is increased, which causes an increase in the size of the power transmission system such that it is difficult to implement optimization of packaging.
Furthermore, an increase in the size of the wheel and the power transmission system may cause space efficiency of a vehicle to be lowered and a bad influence on improvement in fuel efficiency may be provided.